Wax-thread sewing machine



L. E. TOPHAM. WAXIHREAD SEWING MACHINE. APPLICATION FILED JUNE 8, 1911.

.19,994e- PatentedJune20,1922.

6 SHEETS-$HEET l.

L. E. TOPHAM. WAX THREAD SEWING MACHINE. APPLICATION FILED JUNE 8. 1911.

Patented June 20, 1922.

6 SHEETSSHEE T 2- L. E. Tomm- WAX THREAD SEWING MACHINE. APPLICATION FILED JUNE 81' 1911.

1 4193949 9 Patented June 20,1922.

M 6 SHEETS-SHEET 3- L. E. TOPHAMu WAX THREADSEWING MACHINE.-

APPLICATION nuzn was a. 1911.

- PatentedJune 20,1922.

6 SHEER-SHEET. 4.

L. E. TOPHAM. WAX THREAD SEWING MACHINE.

APPLICATION FILED JUNE 8, I917.

Patented June 20, 1922-.

6 SHEETS-SHEET 5- L. E. TOP'HAM. WAX THREAD szwme MACHINE.

APPLICATION EILED JUNE 3. 1911.

Patented June 20, 1922.

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LAURENCE E. TOPHAIVI, O13 SWAMPSGOTT, MASSACH'UISETTS, ASSIGNOB, BY ll/IESNE ASSIGNMENTS, TO UNITED SHOE MACHINERY CORPORATION, OF IPATERSON, NEVT JERSEY, A. CORPORATION OF NEW JERSEY.

WAX-THREAD SEVTING MACHINE.

Specification of Letters Patent. Patented June 2%, 1922. 7

Application filed June 8, 1917. Serial No. 173,537.

To all whom it may concern."

Be it known that I, LAURENCE E. Tommy, a citizen of the United Fntates, residing at Swampscott, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in lVaX- Thread Sewing Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to wax thread sewing machines, and more particularly to machines oi this class provided with a straight hook needle, and devices co-operating therewith to form a lockstitch seam.

The objects of the present invention are to provide machines of above class with a novel and improved construction and arrangement of needle and loop taker and with a loopspreader constructed and operating in an improved and novel manner.

With these objects in view, the features of the invention consist of the novel and improved constructions, arrangements and combinations of parts hereinafter described and pointed out in the claims.

The invention will be readily understood from the accompanying drawings illustrating the invention in its preferred form, and the following detailed description of the constructions therein shown;

In the drawings, Figure 1 is a view in front elevation ot a leather sewing machine embodying the invention; F 2 is a dctail plan view illustrating the forward portion of the head of the machine below the plane of the work support with a section of the casing removed; Fig. 3 is a detail view partly in plan and partly in horizontal section, illustrating particularly the needle mechanism; Fig. 4 is a detail view in vertical section taken substantially on the line 4-4 of Fig. 2; Fig. 5 is a detail view partly in side elevation and partly in vertical section, illustrating the forward portion of the machine below the plane of the work support; Fig. 6 is a detail view illustrating the rotary hook mechanism, taken from the rear of the hook and looking in the di rection of the axis of the hook; Fig. 7 is a sectional view of the hook taken substantially on the line 77 of Fig. 6; Fig. 8 is a detail view, in elevation, looking from the front of the machine substantially in the direction of the axis of the rotary hook, illustrating the thread deflector in acting position and the beak of the hook about to enter the needle loop; Fig. 9 is a view, in

elevation, looking from the right-hand side of the machine, substantially in a direction parallel with the plane oi rotation of the hook, illustrating the parts in the same positions as in Fig. 8; Fig. 10 is a view similar to Fig. 8, illustrating the positions of the parts just as the needle loop is about to be taken from the needle by the beak ot' the rotary hook; Fig. 11 is a view similar to Fig. 9, illustrating the parts in the same positions as in Fi 10; Fig. 12 is a view similar to Fig. 10, except that the thread deflector and needle are omitted, illustrating the rotary hook in a position substantially a quarter of a revolution in advance of that in which it is shown in Fig. 10; and Fig. 13 is a view similar to Fig. 12, illustrating the rotaryhook afterithas advanced slightly less than a quarter of a revolution from the position in which it is shown in Fig. 12.

The invention is illustrated as embodied in a wax-thread lock-stitch sewing machine having the same general construction and mode in"; operation as the machine illustrated and described in applicants Patent No. 1,170,022, dated February 1st, 1916. The machine comprises a vertically reciprocating straight hook needle 2 operating from below the work, a vertically reciprocating straight work feeding awl 4 operating from above the work, a looper 6, a thread-linger 8, a take-up 10, a tension wheel 12, a work support ll, and a presser-foot 16. All of the parts briefly referred to above have the same con struction, arrangement and mode of operation in the present machine as the corre sponding parts of the machine illustrated in applicants patent referred to above. The needle 2 of the machine is a straight hook needle of the usual construction and is removably' clamped in the split upper end of a vertically reciprocating needle carrier 18 mounted in guides in the frame of the machine. The mechanism for actuating the needle comprises a bell crank lever 22, ful

crumed at an on a pin or stud mounted in the frame of the machine, and having an arm 26 which is pivotally connected at 28 to one end of a link 30, the other end of which is pivotally connected at 32 to a collar 35% clamped on the needle carrier. The bell crank lever 22 is oscillated by means of a link 36, one end of which is pivotally connected at 38 to the second arm 40 of said bell crank lever, and the other end of which is pivotally connected at 4.2 to one arm 44 of a second oscillating bell crank lever 46 which is fulcrumed at 4-8 in bearing arms 50 and 52 on the frame of the machine. The bell crank lever 46 is oscillated by means of a link 5a, one end of which is pivotally connected at 56 to the second arm 58 of the latter bell crank lever and the other end of which is journaled upon a crank pin 60 carried by a gear wheel 62 mounted on the forward end of a continuously rotating horizontal shaft 64. The needle actuating mechanism above described operates to advance the needle quickly from its lowermost position through the work, to hold the needle comparatively stationary during the laying of the thread in the hook of the needle by the looper to retract the needle quickly toits lowermost position, and to impart a slight idle movement. or dip to the needle or to cause the needle to dwell while in retracted position, all as fully described in applicants patent referred to above.

The machine illustrated in the drawings is provided with a rotary loop-taking hook, indicated as a whole by the reference numeral 66. The loop-taking hook has the general form of a cylinder, and is rotatably supported in the frame of the machine by means of two plates 68 and 70 secured to the frame, each of which is provided with a semi-circular recess to receive the hook. The semicircular conveXly-cur 'ed edges of the plates fit into a guide groove formed about the periphery of the hook so that the plates form a circular guide or raceway for the hook. The hook is continuously rotated at substan tially uniform speed through suitable con nections from the shaft 64:. A bevel gear 7 2 is formed on the rear end of the hook, the teeth of which mesh with the teeth of a bevel gear 7 f fixed to the upper end of an inclined shaft 76 journaled in a bearing 78 on the frame of the machine. To the lower end of the shaft 76 is secured a second bevel gear 80, the teeth of which mesh with the teeth of the bevel gear 62 carried at the forward end of the continuously rotating shaft 6.4;. The gears 62, 80, 74 and 72 are preferably so proportioned that the rotary hook makes three revolutions during each complete reciprocation of the needle, or during each cycle of operation of the machine.

As is clearly shown in Figs. 2 and 5, the hook is mounted upon the same side of the work support as the needle to the rear of and adjacent to the needle. The plates 68 and 70, which. determine the plane of rotation of the hook, are mounted upon the frame of the machine so that the hook rotates in a plane oblique to the line of feed and intersecting said line at the right of the needle (Fig. 1), and substantially parallel with the line of needle movement. The hook is supported by the plates 68 and 70 at or adjacent to its rear end and its forward or free end, upon which is found a loop-taking beak 82, is directed toward the needle, andis sub stantially unobstructed. lVith this construction and arrangement of the hook, the loop of needle thread may be readily drawn from the hook. The hook is formed with a recess or throat 83 at the base of the beak 82 to receive the loop of needle thread, and with a rib or shoulder 84 extending obliquely from the throa toward the forward end of the hook. which is engaged by one side of the needle loop during the passage of'the same about the bobbin case.

The forward or free end. of the hook supports a stationary bobbin case indicated at Set. The bobbin case has the form of a hollow cylinder closed at one end and provided with a peripheral rib or flange 85 which engages in a groove cut in the interior of the hook. The rib 85 extends for about 270 about the periphery of the bobbin case, and is omitted for the remaining of the pcriphery of the ease, leaving an opening 86 between the bobbin case and the hook to allow the loop of needle thread to pass between the hook and the bobbin case. The bobbin case is mounted in the hook with the closed end thereof directed forwardly toward the needle and with its open end directed rearwardly, so that a bobbin may be inserted through the open rear end of the hook. The open end of the bobbin case is substantially concentric with the rear end of the book. The bobbin is held in position in the interior of the bobbin case by means of a stud 87 threaded into a boss 68 projecting centrally from the closed end of the bobbin case upon the interior thereof. The head of the stud 87 has a split-sleeve-like con- .i

struction, the spaced segmental projections on the head of the stud yieldingly engaging the interior surface of the central bore in the bobbin to hold the bobbin case in position. The bobbin case is held from rotation during the rotation of the hook by means of two reciprocatory retaining pins 90 mounted to slide in guides in a circular casing 92 secured to the plate 68 and extending within the open rear end of the hook (see Fig. 7 The forward end of each of the pins 90 is arranged to engage a groove or notch 9-1 cut in the rear end of the bobbin case. Each of the pins is formed upon its outer side with a. projection 95 for engagement with a cam rib 96 formed upon the interior of the hook. The pins are acted upon by a spring 98 engaging the rear ends of the pins, which acts to maintain the projection 95 in engagement with the cam rib 9G. The spring 98 is made in the form of ring, having two one-turn coils, and mounted on pins 100 extending through said coils. Through the cooperative action of the cam rib 96 and the spring 98, the pins 90 are respectively actuated to disengage their forward ends from the bobbin case at the proper times to permit the passage of the needle loop about the bobbin case. The pins are actuated in timed relation to each other so that there is at all times at least one pin in engagement with the bobbin ease to hold the bobbin case from rotation.

The needle is provided with a thread re ceiving hook, preferably located in the angle between a line extending from the needle in a direction opposite to the direction of feed and a line extending from the needle rearwardly in a direction perpendicular to the line of feed, as clearly shown inFigs. 5, 8, 9, 10 and 11. lVith the needle hook in this position the loop of needle thread drawn out by the needle lies in a plane oblique to the plane of rotation of the rotary hook, and the portion or side of the loop leading from the needle to the preceding stitches is adjacent the hook while the side of the loop leading from the needle to the supply is relatively remote from the hook. For the sake of convenience in description, the side of the needle loop leading to the seam will be termed the work side of the loop, and the side of the loop leading to the supply will be termed the supply side of the loop.

The beak of the loop-taker rotates in a plane at one side of the path of movement of the needle, and in order to cause the beak of the loop-taker to enter the needle loop, the machine is provided with a loop spreader which acts to deflect'the supply side of the needle loop across the path of the beak of the rotary hook. The loop spreader consists of an arm 101 secured to the upper end of a shaft 102 mounted in a bearing 10 1 on the frame of the machine. The end of the arm 101 is arranged to engage the supply side of the needle loop, as the arm is swung rearwardly from the position shown in Fig. 2 upon the shaft 102 as a pivot. The end of the arm is providedwith a projection 106 to engage between the two sides of the needle loop, and with a recess 108 to receiv the supply side of the loop. In the loop spreading movement the arm 101 is swung rearwardly from the position shown in Fig. 2 to that shown in Figs. 8 and 9 the end of the arm being carried to the rear of the beak of the rotary hook, as shown clearly in Fig. 9. During this movement of the arm the end of the arm engages the supply side of the needle loop and deflects the same across the path of the beak of the rotary hook, the bight of thread between the end of the'loop spreader and the needle passing within the path of the beak of the hook and the bight of thread between the end of the loop spreader and the work passing outside of the path of the beak of the hook. During the loop spreading or thread deflecting movement of the loop spreader, the end of the loop spreader is carried into the path of the shoulderS onthe periphery of the hook, and the loop spreader is swungforwardly to carry its end out of the path of the shoulder after the beak of the loophasentered the loop and before the shoulder has come in contact with the endof the spreader. Fig. 8 shows the position i of the loop spreader at the end of its retracting movement. The loop spreader is actuated in the manner described by the movements of the shaft 102 imparted by means of an arm 110 secured to thelower end of theshaft 102, a cam roll 112 secured to the outer end of the arm 110 and a rotary cam wheel or disk llet journaled upon a bearing shaft 116 Socured at one end in the frame of the machine. The axis of the shaft 116 is arranged in alinement with the axis of the shaft Set, and the'cam wheel 11a receives its rotary movement from the latter shaft. To this end the cam wheel is formed with a circular bore or recess 118'in which the end of the crank pin 60 engages.

To enable the bobbins to be removed readily from the bobbin case, the machine is provided with a bobbin ejectorcomprisingan arm 120 secured to one end of a rock shaft 122 mounted in a bearing on the frame. The upper rearwardly directed end of the arm 120 is arranged so that it is projected through the opening 124 in the end of the bobbin case into engagement with the bobbin to remove the bobbin from the retaining stud 87 by the rearward swinging movement of the arm. To the opposite end of the shaft 1.22 is secured an operating handle 125 by which the shaft may be rocked to swing the arm 120 rearwardly to eject the bobbin- The manner in which one side of the loop of thread drawn out by the needle is deflected into the path of the beak of the rotary hook, and the manner in which the loop of needle thread is passed about the bobbin case by the rotation of the hook, are illustrated clearly in Figs. 8 to 13 inclusive. After the needle has retracted from the work, drawing out a loop of needle thread below the work, the supply side of the needle loop is engaged by the end of the loop spreader and deflected substantially into the position shown in Figs. 8 and 9. These ures show the beak of the rotary hook about toenter the needle loop. As'the rotary hook advances from the positions shown in Figs.

8 and 9, the beak of the rotary hook enters the loop of needle thread and disengages the same "from the needle, the loop spreader retracting out of engagement with the thread after the beak enters the loop. Figs. 10 and 11 showthe positions of the parts just as the needle loop is about to be taken from the needle by the action of the hook, the hook having advanced about a sixth of a revolution from the position shown in Fig. 8. It will be noted that the supply side of the needle loop, after the loop is engaged by the beak of the rotary hook, extends from the forward side of the needle rearwardly across the right side of the needle just above the needle barb to the throat 83 at the base of the beak of the hook, and that the beak of the hook at the point in the rotation of the hook illustrated in Figs; 10 and 11 moves in the general direction of the axis of the needle. The rotary hook, therefore, takes the needle loop readily from the needle. During the continued rotation of the rotary hook the bight of needle thread leading from the throat 83 at the base of the beak of the hook to the preceding stitch, which bight lies inside of the beak of the hook, is engaged by the notch 126 at one end of the flange or rib 85 on the bobbin case, and is thereby held from being carried about the bobbin case. The bight of thread extending from the throat 83 to the supply is engaged by the rib or shoulder Set on the periphery of the hook and deflected forwardly until .it extends across the front of the bobbin case, as shown in Fig. 12, in which figure the rotary hook is shown after having advanced substantially a quarter of a revolution from the position shown in Figs. 10 and 11. The rotation of the hook enlarges the loop of needle thread by drawing, thread from the supply, the thread reeving through the throat 83 during the thread drawing action of the hook. Fig. 15% shows the hook after it has advanced somewhat less than a quarter of a revolution from the position shown in. Fig. 12, and illustrates the manner in which one side of the loop of needle thread is carried acrossthe front of the bobbin case and the other side of the loop is carried across the back of the bobbin case by the rotation of the hook. The pins are retracted and advanced at the proper times by the co-operative action of a cam rib 96 and the spring 98 to allow the side of the loop passing across the back of the bobbin case to pass successively between the pins and the case. After the loop of needle thread has been passed. by the rotary hook somewhat past the center of the bobbin case, as shown in Fig. 13, the thread slips from the beak 82, and as the hook completes its rotation the loop is drawn from between the bobbin case and the hook through the recess 86 and the stitch is tightened by the action of the take-up.

Having explained the nature of the invention, and having specifically described a machine embodying the same in its preferred form, what is claimed is:

. 1. A wax thread sewing machine having, in combination, a bobbin case, a rotary hook having a forwardly directed free end provided with a loop-taking beak and operating to pass a loop of needle thread about the bobbin case, a straight hook needle reciprocating in front of the :tree end of the hook and arranged to draw outa loop of needle thread the two sides of which are located at different distances from the plane of rotation of the beak of the hook, and 80 a loop, spreader operating from the forward side or" the needle for engaging the sideo'f the needle loop farther from the plane of rotation of the beak of the loop taker and deflecting it across the path of the beak of the loop taker.

2. A wax thread sewing machine having, in combination, stitch forming devices including a straight hook needle, a rotary looptaking hook having an open and unobstructed rear end and arranged to rotate in a plane oblique to the line of feed, and. a bobbin case. supported in the hook and having an open rear end whereby a bobbin may be inserted or removed through the open ends of the bobbin ease and hook.

3. A wax thread sewing machine having, in combination, a work support, a rotary loop-taking hook located below the work sup port and having its free end directed for- 100 wardly, a straight hook needle arranged below the work support and reciprocating in front of the free end of the hook, and a loop spreader operating from the forward side of the needle and arranged to deflect a loop of thread drawn out by the needle rearwardly into the path of the beak of the hook.

i. A wax thread sewing machine having,

in combination, a bobbin case, a rotary hook having a forwardly directed free end provided with a. loo rtaking beak and operating to pass a loop of needle thread about the bobbin case, a straight hook needle reciprocating in :t'ront'o'f the free end of N5 the hook, and a loop-spreader pivoted on an axis substantially parallel with the needle andarranged to deflect a loop of thread drawn out by the needle rearwardly into the path of the beak of the hook.

5. A wax-thread sewing machine, having, in combination, stitch forming devices including a straight hook needle, a loop-taking hook mounted to the rear of the needle and having an open and unobstructed rear 125 end, and a bobbin case supported inthe hook and having an open rear end concentric with the rear end of a hook whereby a bobbin may be inserted or removed through the open end of the hook.

6. A wax-thread sewing machine, having, the hook and having an unobstructed closed in combination, stitch forming devices inforward end directed toward the needle and eluding a straight hook needle, a rotary loopan open rear end whereby a bobbin may be 1 taking hook mounted to the rear of the inserted or removed through the open ends 5 needle and having an unobstructed forward of the bobbin case and hook. end directed toward the needle and an open rear end, and a bobbin case supported in LAURENCE E. TOPHAM. 

